57 



buffeted by the rapids, the whirlpools, and con- 

 trary currents, they pass through the narrowest 

 channels, avoid the shoals, and rush down with 

 the whole river, guiding the course of the boat 

 in it's accelerated fall." 



In hydrographic descriptions of countries, the 

 vague names of cataracts, cascades, falls, and 

 rapids (saltos, chorros, pongos, cachoeiras, and 

 raudales,) which denote those tumultuous move- 

 ments of water, which arise from very different 

 circumstances of the ground, are generally con- 

 founded with one another. Sometimes a whole 

 river precipitating itself from a great height, and 

 by one single fall, renders the navigation impos- 

 sible. Such is the majestic fall of the Rio Te- 

 quendama, which I have represented in my 

 Views of the Cordilleras ; such are the falls of 

 the Niagara, and the Rhine, much less remark- 

 able for their elevation, than for the mass of 

 water they contain. Sometimes stony dikes of 

 small height succeed each other at great dis- 

 tances, and form distinct falls ; such are the 

 cachoeiras of the Rio Negro, and the Rio Ma- 

 deira, the saltos of the Rio Cauca,and the greater 

 part of the pongos, that are found in the Up- 

 per Maragnon, from the confluence of the Chin- 

 chipe to the village of San Borja. The highest 

 and most formidable of these pongos, which are 

 descended on rafts, that of Mayasi, is how- 

 ever only three feet in height. Sometimes, 



